Making Best Raspberry Swirl Brownies is a simple process. Just follow these steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C) and grease a 9×13-inch baking pan or line it with parchment paper.
2. Melt Butter: In a medium saucepan, melt the unsalted butter over low heat, then remove from heat and let it cool slightly.
3. Mix Sugar and Eggs: In a large mixing bowl, whisk together the granulated sugar and eggs until well combined. Stir in the melted butter and vanilla extract.
4. Combine Dry Ingredients: In another bowl, sift together the flour, cocoa powder, baking powder, and salt.
5. Mix Wet and Dry Ingredients: Gradually add the dry ingredients to the wet mixture, stirring until just combined. Do not overmix.
6. Prepare Raspberry Swirl: In a small bowl, mash the fresh raspberries with the raspberry jam until you have a chunky mixture.
7. Layer the Batter: Pour half of the brownie batter into the prepared baking pan and spread it evenly. Spoon dollops of the raspberry mixture over the batter.
8. Add Remaining Batter: Pour the remaining brownie batter over the raspberry layer, then use a knife or skewer to swirl the raspberry mixture into the batter.
9. Bake: Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
10. Cool: Remove from the oven and let the brownies cool in the pan for about 10-15 minutes before transferring them to a wire rack to cool completely.

These steps will guide you in creating the most incredible raspberry swirl brownies that everyone will love!